docs: def valid_kdf(self, kdf):
          """Determine whether a KDFSuite can be used with this EncryptionSuite.
  
          :param kdf: KDFSuite to evaluate
          :type kdf: aws_encryption_sdk.identifiers.KDFSuite
          :rtype: bool
          """
          if kdf.input_length is None:
              return True
  
          if self.data_key_length > kdf.input_length(self):
              raise InvalidAlgorithmError(
                  "Invalid Algorithm definition: data_key_len must not be greater than kdf_input_len"
              )
  
          return True